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Writer of controversial BBC Halloween special opens up 25 years on

It was the BBC Halloween mockumentary that left thousands of viewers traumatised and led to a tragic aftermath.

Now, 25 years after Ghost Watch was first aired, the creator of a show so controversial it has not been shown on the British network since first being aired has opened up about the conception of the program and the furore that followed.

In 1992, the BBC aired 'Ghost Watch', a supposedly "live" investigation into paranormal activity recorded at a family home in Northold, north-west London.

The Halloween special was the brain child of horror writer Stephen Volk who on the anniversary of the program has spoken to the BBC about the show's conception and the tragic aftermath.

While the show was originally conceived as a six-part drama, Volk says he was asked by producer Ruth Baumgarten to create a 90-minute ghost story.

"I said to her, 'why don't we do it instead as an investigation, a mystery story - pretending it's a live transmission from a haunted house?'," Volk told the BBC.

"I remember that moment very clearly, when she was really excited by that."

The script went through a number of re-writes as Volk wanted to push the boundaries of the horror genre further, wanting it to be fronted by familiar and friendly TV personalities to bring the story to life.

Michael Parkinson was their pick alongside popular children's television presenter Sarah Greene, together with her husband, TV and radio host Mike Smith.

The show was groundbreaking in its use of technology such as an infra-red, heat seeking camera used to "spot" ghostly activity.

The production team also used videotape as opposed to 16mm film in an effort to make it look more homemade.

While media coverage ahead of the show had indicated it was not real, it did not reach everyone. And when one family sat down to enjoy the program together, no one could have foreseen the tragic ending.

April and Percy Denham sat down to watch Ghost Watch with their sons Martin, 18, and Gavin, 14.

Looking back, April and Percy recalled how Martin became agitated throughout the show.

He was hypnotised by the story of Pamela Early and her two daughters being haunted by a poltergeist, fondly named Pipes thanks to the noise it made banging on the pipes.

By the end of the show, Pipes was in control of the TV cameras and was possessing one of the girls.

As the show came to a close, the BBC had its first hint of the controversy that was to result.

The producer revealed to the team the BBC switchboard had been jammed with irate phone calls, with reports of traumatised children.

"I think three women who were pregnant went into labour that evening," Volk said.

"A vicar phoned in to complain that even though he realised it wasn't real he thought the BBC had raised demonic forces.

"It was partly that it scared people, but the complaints were actually more that the BBC had made them feel like mugs.

"People felt the BBC was something they could trust, and the programme had destroyed that trust."

The BBC received thousands of complaints but tragedy was to come.

The Denhams noticed a change in Martin in the days after watching Ghost Watch.

His obsession with the show was compounded by the fact his own house had noisy pipes that banged.

Five days after the show was aired, Martin killed himself, leaving a note that tied his death to the show.

The note to his mother read: "If there is ghosts I will now be one and I will always be with you as one".

A judicial review led to an investigation by the Broadcasting Standards Commission which found the BBC had "a duty to do more than simply hint at the deception it was practising on the audience".

The BBC issued an apology but it was not enough for the Denhams who to this day do not watch BBC channels or anything that features Michael Parkinson.

"It's still just one big mystery and he isn't here so I'm not able to ask him," Mrs Denham told the BBC.

Volk declined to comment on the death of Martin but said he had expected a very different reaction from the audience.

As the writer of the show, Volk said he wished he could have explained his intentions much earlier and said the internet has allowed a discussion around the show to finally happen.

"Suddenly we found a whole pile of people who did like it, they enjoyed it, thought it was challenging and all the things we wanted it to be."